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WRF FDDA Best Practices?

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New member
Hi all,

I'm wondering if anyone can offer or point me to some best practices for using WRF's FDDA nudging options.
Our operational WRF runs use a 36-12-4-1.33 km configuration with nudging on the outer 36km domain.

For my research runs, I'm using a 12 km domain (nudged) with a 4 km domain nested within (not nudged). These are generally short (case study) simulations of 24-48 hours, but I'd like to match observations/analysis as closely as possible.

Is there any advice out there about whether this 12-4 km setup is okay? Or should I ditch the nudging entirely?

Please take a look at the website:
where you can find detailed introduction how to do FDDA, whether ad when FDDA should be conducted for nested domain. etc.
In generally, if you have dense, high-quality observations over your model domain, then FDDA is a good option that may help to improve your simulation. The 12km-4km setting is commonly used in many case studies, and I believe it is appropriate.